1. Field of the Invention
The present invention relates generally to spray thermal management systems for thermally managing electronic devices and more specifically it relates to a spray coolant reservoir system for increasing the efficiency and performance of a spray thermal management system.
2. Description of the Related Art
Modern electronic devices have increased thermal management requirements. Conventional dry thermal management technology (e.g. fans, vents) simply is not capable of efficiently cooling modern high-end electronics.
Spray thermal management technology is being adopted today as the most efficient option for thermally managing electronic systems. U.S. Pat. No. 5,220,804 entitled High Heat Flux Evaporative Spray Cooling to Tilton et al. describes the earlier versions of spray technology. U.S. Pat. No. 6,108,201 entitled Fluid Control Apparatus and Method for Spray Cooling to Tilton et al. also describes the usage of spray technology to cool a printed circuit board. Spray thermal management may be performed locally (i.e. where the chip is sprayed directly), globally (i.e. where the chip and surrounding electronics/boards are also sprayed), a combination of locally and globally, or in conjunction with air cooling or other cooling methods.
One problem with conventional spray technology is that excess coolant is often times retained within the spray chamber to ensure adequate coolant return flow to the pump and to compensate for any coolant leakage. This excess coolant can interfere with the thermal management of electronic devices within the spray chamber. In addition, this excess coolant can also directly impact and damage the electronic components during attitude changes, deceleration and acceleration of the spray chamber.
Another problem with conventional spray technology is that prior to accessing the spray chamber the coolant must be drained which can lead to contamination and coolant loss. A further problem with conventional spray technology is that during acceleration, deceleration and attitude change, temporary coolant loss to the pump may occur thereby decreasing the efficiency of the spray system. An additional problem with conventional spray technology is that the pressure within the chamber varies greatly and is typically dependent solely upon the evaporation of coolant, dissolved gases in the coolant, volume of coolant in spray chamber, and temperature within the spray chamber without adequate control. Another problem with conventional spray technology is that if a leak within the spray system exists there is no automatic method for adding additional coolant to the spray system to compensate for the coolant loss. A further problem with conventional spray technology is that the seal of the spray chamber typically must be broken to fill or add coolant.
While these devices may be suitable for the particular purpose to which they address, they are not as suitable for increasing the efficiency and performance of a spray thermal management system. In these respects, the spray coolant reservoir system according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in so doing provides an apparatus primarily developed for the purpose of increasing the efficiency and performance of a spray thermal management system.